nate stemen

a pal who likes math, physics, and my privacy

This week was a fucking doozy.


I had assignments for Open Quantum Systems (OQS) and Lie Theory due on wednesday night which led to a stressful first half of the week. The OQS homework wasn't too bad and I had done much of it already, but left two hard questions for the last day. The Lie theory homework was just forever long and I was constantly working on it up until 2 hours before it was due when I couldn't anymore. After submitting both homeworks I needed a break and went for a long walk where I ranted to a friend about my struggles and stressed.

This semester I'm definitely struggling with some material which is leading to some frustration towards myself. Some of that frustration is at prof's who seemingly don't care about students, but I'd be lying if I said it all was. You see last semester, even though I took 3 classes, they were all in subjects I'd seen some of before. It was a great transition to being a student again, but I wasn't particularly challenged by the material (except for quantum info.). But this semester it's totally different and everything I'm learning is challenging. I'm feeling a little bit like the expectations in Lie theory are too high (prof even admitted some of the problems are more involved than he intended, and the assignments are long), but again I'm still figuring out the level of struggle that works best with me.

I'm trying my best to make sure the frustration with myself not solving problems doesn't translate into frustration with classes, but I'm not perfect.

We also had our first meeting for the Equity, Diversity and Inclusion committee. It seems like the first meeting was primarily a formality. Hopefully we talk about real things next time. I also went to a talk about “why women leave (physics)”, and on saturday I attended the Diversity in Quantum Computing Conference. Both were really great, although I really dislike weekend conferences. I think I'll have some new/refreshed ideas to bring to our next EDI meeting.


Deleting more data. I also had my annual review and got a promotion from Associate Engineer to Engineer. Normally that would come with a pay raise, but because of this year it may only be very minimal.


Simultaneously busy and relaxed week.


Technically we were on “reading week” this week. I think that normally would mean there are no lectures, but you probably still have all your normal workload? I'm not totally sure, but the “no lectures” thing wasn't even respected which was a little frustrating. It was in Lie theory, but not open quantum systems (OQS). Perhaps since there were so many technical difficulties at the beginning of the course, the prof felt like he needed to make up, but that seems like something he should bare, not the students.

I spent some time watching the lectures for OQS, and starting the homework for that class as well. The questions I've done have been pretty simple, but proving operators to be positive semi-definite really tripped me up. So much so to the point where I even asked a question on physics.SE which I haven't done in ages. It's really simple in hindsight, but I was computing traces incorrectly for a while. I even sent some of my partial homework write ups to Kevin (math PhD student at Boston College) and he reminded me how crazy physicists are for both not specifying sum limits, and playing with objects with 4 indices. It's a good reminder that even in some areas of math, that would be way too complex. Funny how that works.

I also made some progress on my Lie theory homework, and thankfully the prof put some questions on this homework that are actually quite simple. At least I hope so. It's making me realize the importance of simple questions as means of confidence boosters. The past two assignments have me struggling on almost every question, and it feels nice not to have that here. Solving a problem without resorting to asking around is really rewarding.


I worked quite on this $\mathsf{SU}(2)$ problem, and did some writing about and some coding. I'll be sharing the notes I'm writing internally for some feedback soon. Hopefully I don't write too many basic things for them. Either way it's really helped me understand the problem so that's great.

Also been fun coding in python again. I'm using sympy which I've never used before and good ole numpy which I like, but haven't used in a while.


Pretty slow week work wise, but it was welcomed to go along with my reading week. I have my annual review tomorrow so did some prepping for that, and in the meantime just kept chugging along with deleting data.


I'd like to start trying to write more frequently, and maybe if I commit to writing weekly that will help me.


The beginning of week was mostly spent working on my Lie groups/algebras homework. That class has been super interesting so far, but a few things have been bothering me.

  1. the prof gives way too much homework
  2. the class is going a bit too fast, especially for how much homework is being given
  3. only posting pre-recorded lectures feels lazy to me

I'll explain a bit more what I mean by the last point. When classes were in person (oh so long ago), being in the same place physically gave students a way to have low effort interactions. In my opinion those interactions often lead to things like study groups, casual hangouts, random math chats etc. In an online environment it's surely harder to mimic that, but it's not impossible. By only posting pre-recorded lectures, and then dipping out you're doing the bare minimum in “education”, but you're not providing a space for students to learn. That to me has been really frustrating this week because both my classes are this way.

To make up for the lack of math chats in my life I've gone to a lot of office hours, and formed a small study group in one of my classes, but I'm mostly saddened by the fact Prof's aren't taking more responsibility here. I could go on and explain why I think this is the case, but I'll save that for another time.

After that Lie groups/algebras HW was due wednesday, I transitioned to Open Quantum Systems where I haven't done much for the course. I'm really looking forward to getting more into it, but we haven't actually had that much to do!

I've also been doing a bit of research work on this $\mathsf{SU}(2)$ decomposition problem that Joel gave me. I haven't made much concrete progress on a solution, but I've learned a whole lot while figuring out what the problem even is. I think I have a good grasp on it now, but not sure I have much direction to figure out where to go. Thankfully I'll be chatting with Joel and Matthew next week for some guidance.


Still chugging along on some data removal and S3 cleanup tasks. It's quite fun at this point because it feels like digital landscaping. Or purging. Like running rm -rf on a big folder. Pretty satisfying watching (unecessary) data go down the drain.


I've finished my first semester of graduate school at the University of Waterloo where I study quantum computation. It's been a ride; let me tell you about it.

A little background

Prior to August 2020, I was a full time software developer at Overleaf, and before that I did my bachelors at NYU in mathematics and physics. After 2.5 (lovely) years as a developer I decided it was my time to make graduate school a reality and applied to 15 schools. After a few rejects, and much consideration I decided on U Waterloo for many reasons, but that's for another time. I also decided to continue working for Overleaf part time to help me make a few more bucks, because being a grad student is pretty destitute. Being out of academia for 3 years certainly made me have my doubts if I was going to be able to succeed at school. I had done some data-science work as a developer, but I hadn't really done much of any math, and definitely no quantum mechanics since my undergraduate.

Before starting school I took a month off work to mostly relax and decompress from working, but did also start prepping a little bit for school. Mostly just some elementary reading on quantum computation (I had never formally studied the subject mind you!), and a little refresher of some basic quantum theory. Starting out, I was mainly worried I wouldn't be as good at math as I once was, but I fell quickly into the swing of things.


For my first semester I took three courses:

  • Numerical Analysis
  • Advanced Quantum Theory
  • Introduction to Quantum Information Processing

It seems like most graduate students at U Waterloo take two, but being an international student, the university did not allow me to be a teaching assistant for this semester, so I had a few extra hours per week and thought I could squeeze in an extra course. I chose these three courses for specific reasons:

  • Numerical analysis because of the programming component and that's what I've been doing for the past few years, hence making it not too hard a course
  • Advanced Quantum Theory (which is a cross listed undergrad/grad course where the grad students have an extra project to do at the end) because I hadn't looked at anything quantum for the past 3 years and needed a refresher
  • Quantum Info. Processing because that's the first course in the quantum info track I'm on and it would help me get into research faster

Looking back on the semester, I feel like it was a great selection of courses; it did what I intended, which was help me transition from a working life, to that of a student. Three courses was a bit much, especially on top of working part time (8hrs/week), but it was manageable. I'm certainly looking forward to having a smaller workload in future semesters.

Day to Day Life

Two of my classes (quantum theory, and quantum info) posted recorded lectures on youtube, and in numerical analysis we had live lectures over zoom. All three courses used piazza as a Q&A forum. The youtube lectures were great, but left a lot to be desired in terms of social interaction. I didn't really meet anyone in my quantum theory course, and only managed to meet some friends in quantum info because we set up a study group (shout out Chelsea and Wilson). In numerical analysis the professor had a 15 minute period before class where he encouraged people to “show up and hang out” and chat mostly about non-math stuff, but anything really. As a new student who knew almost no one, I really appreciated it as a way to see some faces and maybe start the process of a friendship.

Most days I would watch one or two lectures, and then primarily work on homework, and oh my god was there a lot. I did a total of 24 problem sets (which you can checkout here:, of which many of the quantum theory ones were pretty tedious. Other than the few tedious calculations I learned a lot from homework, but 3 classes didn't leave me with much time to really dive into anything very deeply (even though I wanted to). That said, this was my first semester and was intended to help get me settled and adjusted. In the future I'll be able to give more time to topics I find interesting.

Overall, working remotely for the past few years prepared me well to get through some of the struggles of online classes (e.g. I really don't have a problem speaking up in online meetings), but learning can be hard when you aren't surrounded by people who are doing the same thing. This was by far the biggest struggle of the semester. Having friends you can talk to about things your learning is so helpful in processing, and digesting material. Big ups to Kevin (also a first year math grad student) who chatted with me a bunch through the semester.

Compared to Work

At the start of the term, I was so happy to be a student again. Life as a student is pretty different from that of a working person; mostly life is much simpler. Problems I faced at work don't often have nice succinct solutions, but rather require analyzing trade-offs and understanding how decisions will affect other arms of the organization. That said, studenthood is much more manicured, and the experience isn't as “disheveled”. Problem sets almost always have “correct” answers, and professors lead you along from one topic to the next. Life is a lot more decided than it was for me when I was working. This “simplicity” was fun and exciting in the beginning, and still is to some degree, but it becomes tiring too. The lack of autonomy can sometimes be a drag, but I remind myself I only have to do 8 courses (3 of which are now done!) before I get to focus on research and have more autonomy there.

The biggest suck about school life is by far the exams. Working was very rarely stressful for me, but exams are stress multipliers. I don't think grading is ever very accurate, but exams must be worse than everything else. Taking an exam for the first time in 3 years wasn't a fun experience and brought back all the memories we drop when we nostalgize about being a student.

Life Outside

Since grad school has been on my to do list for a long time, I definitely poured myself into it fully this semester. That said I also tried to recognize the importance of doing non-school things and taking breaks from work. I definitely don't feel burnt out, but I could do slightly better at this next semester. Here are some highlights from non-school life:

  • read a non-fiction book
  • read some poetry
  • wrote some poetry
  • got outside a good amount in the beginning of the semester
  • cooked a lot of yummy food
  • saw my family (and a few friends) (yes, safely)
  • listened to a lot of good music

Some things I could do better with moving forward are

  • getting outside and getting exercise regularly (god I miss rock climbing with my friends)
  • spending more time with my partner, preferably without a homework assignment in hand
  • spending less time in front of the computer
  • I'm sure many more, but I'll focus on these for now.

It's been a crazy year. Head over to to see some pictures I put together to commemorate making it partway through a pandemic.

Hello world.

I've tried to start a blog a few times and they've all failed. In an effort to have this one not be one post, and then disappear forever, I'd like to try and diagnose what went wrong previously.

First, I have to admit I'm a perfectionist and not the good kind. The kind that prevents myself from finishing things because I have much grander goals than I can currently accomplish. For example one of my first attempts to start a blog was using Github pages with Jekyll. Now those are both great tools, but I had this idea that might blog had to be unique in certain ways that those tools wouldn't allow, and hence I wrote one post (about perfectionism funnily enough) and then never came back to it because it felt like it didn't fit me. I've had a hard time for a long time with taking action when something at the base doesn't feel right. Even when learning new things I find it hard to build on knowledge when my foundation doesn't feel solid. This has sometimes resulted in race to the bottom, and at times made me consider studying logic/set theory. That said, sometimes it's totally fine to push forward without everything being crystal clear. In fact that's already what we do most of the time! From this perspective I think this site can be viewed as an exercise in tamping out some of my perfectionist tendencies.

Second reason previous attempts at blogging have failed: I feel like I don't have that much to say. At least stuff that hasn't already been said on the internet. So if that's the case why am I here? Well I guess this could be considered an exercise in self-esteem and confidence building. Even if no one reads this, I'll feel like at least I made an effort, and at least I did the thing I've thought a lot about doing.


Since undergrad, where I let a lot of nerdy friends who introduced me to the internet beyond facebook, email, stackexchange, and youtube, it's intrigued me how cozy the internet can feel. People's personal webpages, and all sorts of funky content people generate for fun is simply amazing. I always wanted to be more involved in communities like that, but never had the technical knowledge to get into having my own website. Fast forward to graduating college and I somehow managed to land a developer internship. That introduced me to even more of what the web is capable of, but even though I had learned about HTTP/SSL, javascript and all sorts of things fundamental to the internet, I still didn't feel like I belonged in some sense. That might sound strange, especially if you know I'm a white guy (and geez is the internet and it's communities filled with white guys), but everyone I was seeing was so confident. Whether it was technical articles about setting up reverse proxies, or opinions on politics, everyone on the internet seemed like they were trying to win arguments, and not engage with anyone. I think that was the reason I felt like I didn't belong. And it wasn't a massive like “you don't belong here” feeling, but more like “I don't talk like that, and hence I won't belong” feeling.

Digressing, what I'm getting at here is that I always wanted to see people who were more uncertain about things on the internet. This shouldn't be a space only for those who think they know what they're talking about (because a lot of the time, maybe they don't, idk).

Also, now that I'm in grad school, something feels different. As a junior developer, I didn't think people would care much about what I had to say, but maybe now that's different? I'm not sure that really matters though because I'm not here to write for huge audiences. Hopefully just a few.

Anyway, this has been fun writing, and for that it's been totally worth it. I'm hoping this won't be the only post this time around. I already have a few ideas for posts I want to write, so hoping that keeps me going.